Something that really, really gets to me is that I have to be happy for some people. I don't want to be happy for certain people who've hurt me or have discarded our friendship for someone else. I know it's petty but I prefer to deal with it that way instead of faking a smile.
No, I'm not happy you found someone. I'm not happy you met someone online. I'm not happy you're spending time with them. I'm not happy you only talk to me when your boyfriend isn't around and you're bored. I'm not happy you're revolving your life on this new relationship when in reality, you've just shut off your social circle.
No, I'm not happy for you.